Cooling apparatus



UNITED STATES; PATENT OFFICE.

Ernest F. Miller,

tus, more particularly to a l tem for refrigerating appar 2,088,381 4ooonmo APPARATUS Westinghouse Prospect Park, Pa., assignor to Electric &Manufacturing Company, .East Pittsburgh, Pa., a corporation ofPennsylvania Application April 20, 1934, Serial No. 721,475- 1 8 Claims.(01. 62-152) My invention relates to refrigerating apparaiquidcirculating sysatus of thesteam or vapor jet type, and it has for anobject to provide improved forth.

A further object is to pro apparatus of the character set vide, inrefrigerating apparatus of the vapor jet type embodying an evaporativecondenser, imp

roved means for removing condensate from the condenser and fordelivering said condensate and unevaporated water for effectingevaporative cooling of the condenser.

A further object is to provide means for readily draining the liquid froprevent freezing thereof in other purposes.

- In accordance with my in the .apparatus to cold weather or forinvention, I use the condensate formed in the condenser to provide asupply of liquid to efiect evaporative cooling of the condenser,preferably as a spray for wetting the air-cooled surfaces of thecondenser.

which is not evaporated I also drain the liquid and add the same to thecondensate'before supplying the same to said spray.

A single pump serves to removecondensate deliver the condensatepressure'to the spray.

from the condenser and to and additional water under The unevaporatedwater is of the pump, afloat valve thereof to maintain a given inlet ofsaid pump, while all mitted to flow uncontrolled to returned to theinlet controlling the flow s'ubmergence on the condensate is persaidinlet.

I also provide means for supplying condensate from the condenser to theevaporator to replace liquid therein. I withdraw the stream ofcondensate of thepump before the this condensate from flowing to theinlet unevaporated spray water is added thereto, whereby only pure codensate is admitted to the To drain the water from the apparatus, Iproevaporator.

vide a drain conduit connected: to each of the several pressure regionsof the apparatus and having a single discharge valve, preferably maneually operated, so that the water may be drained by opening the onedischarge valve. A check valve isprovided in each connection except thatcommunicating with the region containing the highest pressure when theapparatus pressure,

tion. The latter is in operathrough the drain conduit, closes the checkvalves to isolate the several pressure regions from each other duringoperation; v The above and other objects are effected by my invention aswill be ap parent from the folof refrigerant open ends of the tubes M.The refrigerant is communicated lowing description and claims taken inconnection with the accompanying drawings, forming a part of thisapplicatiomin which:

The single figure is a diagrammatic view, in

elevation, of apparatus embodying my inven- 5 tion. Referring to thedrawing in detail, I show an evaporator l0, which also serves, in thiscase, to cool air directly. The evaporator includes a casing II, upperand lower headers l2 and i3, 1 and cross-finned tubes l4 extendingbetween said headers and providing free communication therebetween. .Theinterior of the headers and the tubes constitutes the evaporatingchamber. The casing I l is formed with an inlet l5 and an 5 outlet l6for the passage of fluid to be cooled, such as air, in contact with theouter surfaces of the tubes. A manifold l1 and a. plurality of spraynozzles l8 mounted thereon are provided in the upper header I 2 andarranged to direct a spray liquid particles into the upper usuallywater, which liquid will be referred to. I hereinafter withoutrestricting the invention thereto. An ejector or. thermal compressor I9is provided to effect a reduced pressure within the'evaporating chamberby removing vapor, therefrom, and has its suction inlet 2| connected, inthe illustrated embodiment, to the lower header l3 through a'conduit-22. Vapor for motivatingdshe ejector, usually steam, is supplied to the.ejector through a conduit 23. 1 A condenser 24 is connected to theoutlet of the ejector for condensing the vapor discharged therefrom,including the vapor withdrawn from the evaporating chamber and theexpended moheaders 25 e 40 being connected to the means (not shown) arecondensed, the header 25 ejector outlet. Suitable provided for removingair and non-condensab1e gases from the condensing space of thecondenser. The cooiing fiuid, which is preferably air, is circulated incontact with the outer surfaces of the'tubes by a fan 28. Viewing theapparatus as seen on the drawing, the direction of flow of the coolingair is either forwardly or rearwardly.v To increase the cooling effect,I provide evaportive cooling of the condenser tubes. Nozzles 28, carriedby upper and lower manifolds 3i, are provided to spray water intothecirculating air stream and onto the outer sur- The nozzles arearranged in lthrough a conduit 4| livery under pressure to the condenserspray nozzles 29 of the remaining condensate and of unevaporatedcondenser spray water. The lower header I3 of the evaporator is formedwith a drain outlet 32 connected, through a conduit 33, to the inlet ofa water circulating pump 34. The outlet of said pump is connectedthrough a conduit to the nozzle manifold l1.

'The condensateformed in the condenser collects in the headers 25 and 26which are connected to a drain conduit 36, through which the condensateflows downwardly by gravity. The conduit 36 is connected to the conduit33, through parts presently described, for the purpose of supplyingmake-up water "to the evaporator; that is, water for replacing thatevaporated in the evaporator. The conduit 36 has a branch 36a which isconnected to a float chamber 31. A float valve 38, actuated by a floatmember 39 within said chamber, controls the flow of liquid from thebranch conduit 36a into the float. chamber. The latter is connected withthe conduit 33 for supplying liquid thereto. The float valve 38 servesto control the flow of condensate to the conduit 33 to maintain apredetermined level of liquid within the float chamber 31, the valvedecreasing the flow of condensate as said level tends to rise andincreasing said flow as the level tends to drop. The upper partof thefloat chamber 31 is connected to the evaporator, at any suitable pointsuchas the header 12, through a vent pipe Y 42. The same level of liquidis maintained, therefore, within the conduit 33 and the float chamber31. r

The conduit 36 is also connected, through a branch 36b, to a conduit 42,which conveys the remaining condensate to the inlet of a circulatingpump 43. The pumps 34 and 43 may be gear pumps, as shown, and aredesirably driven by a common source of power, such as an electric motor40. The pump 43 discharges water under pressure to a conduit 44, whichconveys the same to the nozzle manifolds 3|. Only a small portion of thewater sprayed onto the. condenser tubes at one time is evaporated, sothat it is necessary to recirculate the unevaporated water. This watercollects in a sump 45, from which it flows through a conduit 46, a floatchamber 41, a conduit 48, a float chamber 49, and a conduit 5|, to theconduit 42', which it is added to the condensate flowing to the pump 43.

Within the float chamber 41 is a float valve 52 having a float member 53controlled by the levl of liquid in the float chamber. The purpose ofthe float valve 52 is to prevent the admission of air from theatmosphere to the condenser through the water'circulating conduits inthe event that the quantity of unevaporated spray water in the floatchamber 41 is insufiicient to immerse the end of the conduit 48. As thewater level in the float chamber 41 drops, due to any suchinsufficien'cy, the float member 53 moves the valve 52 in closingdirection, thereby preventing drop in water level below a.predeterminedpoint.

densate formed in the condenser and not sup- A drain conduit 54 isconnected to the upper portion of the float chamber 41, to drain oiTexcess water when the quantity of unevaporated spray water exceeds thequantity required by and admitted to the pump 43.

Within the float chamber 49, there is provided a float valve 55, thepurpose of which is to limit the admission of unevaporated condenserspray water to the conduit 42 to an amount which, together with thecondensate flowing thereto from the condenser does not exceed thecapacity of the pump 43, thereby assuring that all condensate will beremoved from the condenser. The float valve 55 includes a float member.56 responsive to the level of liquid in the float chamber 49, whichlevel is on the down-stream side of the valve 55. Upon drop in Waterlevel, the valve 55 moVesin-Opening direction to admit more water,tending to maintain said level substantially constant. The upper portionof the float chamber 49 is connected through a'vent pipe 51 to theheader 25, so that the liquid within the conduit 36 and the floatchamber 49 will be at the same level. It will be apparent that allconpied to the conduit 33 may flow unrestricted to the pump 43. Anyincrease in the quantity of condensate will tend to raise the level ofthe liquid in the float chamber 49 and restrict the admission ofunevaporated condenser spray water.

The operation of the above-described appa-ratus, which will be apparentfrom the above description, is as follows: The water sprayed from thenozzles l8 in the evaporator I0 flows 3 downwardly through the interiorof the tubes l4, a portion of said water. being evaporated by the heatextracted from the air flowing over the tubes. The vapor is withdrawnfrom the evaporator by the ejector l9 and discharged, together with theexpended motive fluid, into the condenser 24. The unevaporated watercollecting in the lower header l3 flows by gravity through the conduit33 to the pump 34, by which it is recirculated through the conduit 35 tothe nozzles I8. Due to the continual evaporation of a portion of thewater, the total quantity in the circuit just described would tend todecrease, thereby lowering the water level in the conduit 33 and thefloat chamber 31. The float member 39 responds to the drop in waterlevel by opening the valve 38 to admit a quantity of condensate from thecondenser 24 which is suflicient to maintain said water levelsubstantially constant and which replaces the water evaporated withinthe tubes l4. 5

The remainder of the condensate from the condenser flows unrestrictedthrough the conduits 36, 36b, and 42' to the pump 43, by which it iscirculated through the conduit 44 to the spray nozzles 29. From thelatter it is directed onto the exterior surfaces of the condenser tubes21 to provide evaporative cooling of said tubes. Inasmuch as thequantity of water circulated by the pump 43 is considerablyin excess ofthe quantity of condensate formed level of liquid within the conduit 36and the float chamber 49 will tend to drop. The float member 56 isresponsive to the drop in level and opens the valve 55 to admit suchquantity of unevaporated spray water as is required to maintain '41substantially the same level, thereby providing the required amount ofwater to be circulated by the pump 43. When the total quantity ofunevaporated spray water returned through the conduit 46 exceeds thecapacity of the pump 43, the 7 within the condenser, the

flow to the pump. In this case, a quantity of water less than thecapacity of the pump 43 is circulated by the pump. In an installation inwhich the quantity of unevaporated spray water or other spray ofadditional liquid, taken to-' ether with the condensate flowing to thepump, is always less than the capacity of the pump 43, the valve 55 maybe dispensed with, and in an installation in which it is always greaterthan the capacity of the pump 43, the valve 52 may be omitted. It willbe apparent, therefore, that I havemade provision against flooding thecondenser by the admission of an excess quantity of water to the inletof the pump and that I have also' made provision against the admissionof air into the condenser upon a deficiency in supply of unevaporatedspray water or other liquid.

It will be noted that the condensate which is supplied to the evaporatoras make-up to replace evaporated liquid, is withdrawn through theconduit 350 before the portion of the condensate flowing to the pump 43through the conduit 36b is mixed with the unevaporated spray water.- Inthis way, the impurities and dissolved air which the unevaporated spraywater may have acquired in the spray is prevented from entering theevaporator.

The apparatus described may be used for any suitable application whereair cooling or other cooling is required; for example, it may beinstalled on a railway passenger car for cooling the air therein.

A further feature of my inventionresides in the provision of means forreadily draining the water or other liquid from the system, in order topreventfreezing and damage to the apparatus in cold weather. Thisprovision is particularly applicable to passenger railway cars whichmove between widely varying climates. I provide a drain conduit 62,which discharges into the drain conduit 54 and which is provided with asingle discharge valve 63. Branch conduits 51',-58, 59, 6E, and BIconnect the conduits 3.5, 33, 42, and 44, and the float chamber 41,respectively, with v the drain conduit 62, the points of communicationwith the latter conduits being adjacent the lowermost points thereof sothat water may readily flow therefrom by gravity. In each of the branchconduits 51, 58, 59, and 6|, I provide a check valve'64 which permitsdownward flow o1 water into the drain conduit 62,- but which preventsupward flow of water. The branch conduit 60 communicates with theconduit 62' which contains the highest pressure within the apparatuswhen it is in operation, and no check valve is placed in this branchconduit. When the apparatus is in operation, the maximum pressure of thesystem in the conduit 44 is communicated through the branch conduit 60to the drain conduit 52 and imposed on the check valves to close thesame, thereby isolating the several pressure regions represented bysaid'condliits from each other. In this case, the dischargevalve 6 3 isclosed. When operation of the apparatus is discontinued, the

, spraying liquid onto the air pressures within the system are releasedand all of the check valves are free to open. If the discharge valve 63is opened in this case, water may flow by gravity from the severa1portions of the apparatus through the respective branch conduits intothe drain conduit 62, and through the discharge valve 63 into the drainconduit 54.

It will thus be seen that I have provided a simple drain arrangementwhereby the apparatus may be completely drained of liquid by theopeningof a single valve. I

While I have shown my invention in but one form, it 'Willbe obvious tothose skilled in the art that it is not so limited, but is susceptibleof various changes and modifications without departing from the spiritthereof, and I desire, therefore, that only such limitations shall beplaced thereupon as are imposed by the prior art or as are specificallyset forth in the ap pended claims. I

What I claim is:

1. The combination with a condenser, of a pump having its inlet disposedat a level below the condensate outlet of said condenser and connectedthereto, whereby condensate flows by gravity from said condensate outletto the inlet of said pump, means connected to the outlet of said pumpand utilizing the liquid discharged.

therefrom to provide evaporative cooling of said condenser, and meansfor supplying additional liquid to the inlet of said pump includingmeans responsive to the head of liquid on the pump inlet for regulatingthe supply of said additional liquid to maintain a given submergenceonsaid pump.

2. In vapor jet refrigerating apparatus, the

combination of anevaporator, an ejector for re-,

moving vapor-from said evaporator to effect cooling by evaporation ofliquid therein, an air cooled condenser for condensing the gaseous fluiddis-- charged by the ejector, a pump for withdrawing condensate from thecondenser and for spraying the same onto the air cooled surfaces of thecondenser, drain conduit means communicating with the discharge side ofsaid pump, a single valve controlling discharge of liquidtherefrom,'aconnection between the evaporator and the drain conduitmeans, a connection between the inlet side of the pump and the drainconduit means,

and means responsive to fluid pressure developed by said pump forclosing communication through said connections. v

31 In vapor jet refrigerating apparatus, the combination of anevaporator, an' ejector for removing vapor from said evaporatortoefiectcooling by evaporation of liquid therein, .an air cooledcondenser for condensing charged by the ejector, a pump for withdrawingcondensate from the condenser and for spraying the same onto theair-cooled surfaces of the condenser, drain conduit means communicatingwith the discharge side of said pump, a single valve controllingdischarge of liquid therefrom, a connection between the evaporator andthe drain conduit means, a connection between the inlet side of the pumpand the drain conduit means, and a check valve in each of saidconnections arranged to permit flow into said drain conduit means and toprevent flow in the opposite direction, said valves being closed innormal operation by the pump discharge pressure.

4. The combination of an evaporative condenser, means including amechanical pump for cooled surfaces of said condenser, said pump havingits inlet connected to the condensing space of the condenser the gaseousfluid disdenser, of means for and being effective to remove condensatetherefrom, and means for delivering unevaporated spray water to theinlet of said pump at subatmospheric pressure, said pump imposingsufficient pressure on said condensate and unevaporated spray water forspraying the same against atmospheric pressure.

5. The combination with an evaporative condirecting liquid onto the aircooled surfaces of the condenser to provide evaporative cooling, amechanical condensate removal pump having its inlet connected to thecondensing space of the condenser for receiving condensate therefrom,means for delivering unevaporated liquid from said air cooled surfacesto the inlet of the pump at sub-atmospheric pressure, and meansresponsive to the head of liquid on the inlet of the pump forcontrolling the flow of said unevaporated liquid thereto, saidcondensate pump being effective to deliver said condensate andunevaporated liquid under pressure to said first-mentioned means.

6. The combination with an-evap0rative condenser, of means for directingliquid onto the air cooled surfaces of the condenser to provideevaporative cooling, a mechanical condensate removal pump having itsinlet connected to the condensing space of the condenser for receivingcondensate therefrom, means for delivering unevaporated liquid from-saidair cooled surfaces to the inlet of the pump at sub-atmospheric pressureand mixing the same with the condensate, and means for extractingcondensate at a point ahead of the point of mixture so as to provide asupply of pure condensate, said condensate pump being effective todeliver said condensate and said unevaporated liquid under pressure tosaid firstmentioned means- 7. The combination with an air cooledevaporative condenser, of a pump for withdrawing condensate from thecondenser and for delivering liquid under pressure for supplying the aircooled surfaces of the condenser, drain conduit means communicating withthe discharge side of said pump, a single valve controlling discharge ofliquid therefrom, a connection between the inlet side of the pump andthe drain conduit means, and means responsive to fluid pressuredeveloped by said pump for closing communication through saidconnection. 1 a

8. The combination with an air cooled evaporative condenser, of a liquidunder pressure for supplying the air cooled surfaces of the condenser,drain conduit means communicating with the discharge side of said pump,a single valve controlling discharge of liquid therefrom, a connectionbetween the inlet side of the pump and the drain conduit means, and acheck valve in said connection arranged to permit flow into said drainconduit means and to prevent flow in the opposite direction, said checkvalve being closed in normal operation by the pump discharge pressure.

- ERNEST F. MILLER.

pump for withdrawing condensate from the condenser and for delivering

